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Direct and converse magnetoelectric effects are two opposite processes, which were integrated in a model based on equivalent circuit. Following the piezoelectric and magnetostrictive constitutive equations, we obtained magnetic-mechanical-electric equations, and then built a symmetric equivalent circuit about the magnetoelectric coupling. We equivalently analyzed the direct and converse magnetoelectric effects with this equivalent circuit. The numerical calculations fit the reported results very well, including the magnetoelectric changes with the thickness ratio and frequency, the relative lower converse magnetoelectric resonance frequency, and the phase increase of π around the direct and converse magnetoelectric resonance frequencies. This model helps us understand the magnetoelectric properties deeply, especially for the converse magnetoelectric effect. [ABSTRACT FROM AUTHOR]

Electric-field-induced magnetization (EIM) characteristics are investigated in a small 0.68[Pb(Mg1/3Nb2/3)O3]0.32PbTiO3/Terfenol-D bilayered composite by using double coils in a wide frequency range of 10–700 kHz. The EIM behaviors are strongly dependent on driving electric field frequency, bias magnetic field, and angle θ between the bias magnetic field and polarization direction. The magnetoelectric coefficient at electromechanical resonance frequency of 185 kHz reaches up to 3.1×10-7 s/m, which is ∼60 times higher than the values at nonresonance frequency. The EIM variations with the bias magnetic field exhibit hysteresis, forming EIM hysteresis loops caused by the magnetostrictive hysteresis from Terfenol-D. [ABSTRACT FROM AUTHOR]

Bilayer multiferroic nanocomposite films of Pb(Zr0.52Ti0.48)O3 (PZT) and Co0.9Zn0.1Fe2O4 (CZFO) were prepared on general Pt/Ti/SiO2/Si substrate via a simple solution processing. Different growth sequences of PZT and CZFO on the substrate yielded two kinds of bilayered structures, i.e., PZT/CZFO/substrate. and CZFO/PZT/substrate. Structural characterization by x-ray diffraction and electron microscopies showed good surface morphology and interfaces of these bilayered thin films. Strong ferroelectric and ferromagnetic responses were simultaneously observed in the bilayered thin films, depending on their structures. [ABSTRACT FROM AUTHOR]

Double-layer magnetoelectric CoFe2O4 (CFO)/Pb(Zr0.52Ti0.48)O3 (PZT) nanocomposite thin film was prepared via a pulsed-laser deposition. X-ray diffraction showed that there are no other phases but PZT and CFO phases in the film. The smooth film surface was obtained after depositing the CFO and PZT layers. The double-layer thin film exhibits both good ferromagnetic and electric properties, as well as a magnetoelectric coupling effect. The magnetic-field-induced polarization in the thin film is zero below the dc magnetic field of 800 Oe and keeps constant above 800 Oe, and is strongly dependent on the ac magnetic field frequency which drives the magnetic domain rotation and then the electric polarization in the PZT layer. [ABSTRACT FROM AUTHOR]

Investigates the improvement in the corrosion resistance of cation substituted yttrium barrium[sub 2]copper[sub 3]oxygen[sub 7-delta thin film. Reactivity behavior of cation substituted thin films; Correlation between corrosion resistance and degree of cation substitution; Factors causing corrosive resistance enhancement.

Examines the intrinsic reactivity characteristics of common copper-oxide superconductors. Use of x-ray diffraction, scanning electron microscopy, x-ray photoemission spectroscopy; Results of electrochemical and four-point probe measurements; Formation of single phase products.

Observes the photo-assisted structural transition and oxygen diffusion in solid C[sub 60] films. Application of Raman scattering technique; Use of alpha resonance scattering to detect oxygen diffusion; Comparison between oxygen-doped C[sub 60] and oxygen free fcc C[sub 60].

Demonstrates the surface-emitting laser-based optical bistable switching device. Electro-optical characteristics of the photothyristor; Application of low-pressure metalorganic vapor phase epitaxy; Control of the positive feedback in the photothyristor.

Demonstrates the performance of latchable optical switch and logic gates. Integration of a vertical-cavity surface-emitting laser with heterojunction photothyristors; Achievement of excellent optical switching characteristics.

Analyzes the plasma-shifted distributed feedback laser with linearly chirped grating. Calculation of the field distribution, threshold gain difference between the lasing mode and the next lowest threshold gain mode and the linewidth of the lasing mode; Locking of the lasing mode pattern and the carrier concentration distribution at high injection level.